[Merge to M56] Fix the Crash in the launcher's start page on Chrome OS.

ui/app_list/views/start_page_view.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/app_list/views/start_page_view.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/i18n/rtl.h"
@@ skipping 172 matching lines @@
 
   std::vector<SearchResult*> display_results =
       AppListModel::FilterSearchResultsByDisplayType(
           results(), SearchResult::DISPLAY_RECOMMENDATION, kNumStartPageTiles);
   if (display_results.size() != search_result_tile_views_.size()) {
     // We should recreate the grid layout in this case.
     for (size_t i = 0; i < search_result_tile_views_.size(); ++i)
       delete search_result_tile_views_[i];
     search_result_tile_views_.clear();
     RemoveChildView(all_apps_button_);
-    CreateAppsGrid(std::min(kNumStartPageTiles, display_results.size()));
+    CreateAppsGrid(display_results.size());
   }
 
   // Update the tile item results.
   for (size_t i = 0; i < search_result_tile_views_.size(); ++i) {
     SearchResult* item = nullptr;
     if (i < display_results.size())
       item = display_results[i];
     search_result_tile_views_[i]->SetSearchResult(item);
     search_result_tile_views_[i]->SetEnabled(true);
   }
 
   Layout();
   parent()->Layout();
   // Add 1 to the results size to account for the all apps button.
   return display_results.size() + 1;
 }
 
 void StartPageView::StartPageTilesContainer::UpdateSelectedIndex(
     int old_selected,
     int new_selected) {
-  if (old_selected >= 0)
+  if (old_selected >= 0 && old_selected < num_results())
     GetTileItemView(old_selected)->SetSelected(false);
 
-  if (new_selected >= 0)
+  if (new_selected >= 0 && new_selected < num_results())
     GetTileItemView(new_selected)->SetSelected(true);
 }
 
 void StartPageView::StartPageTilesContainer::OnContainerSelected(
     bool /*from_bottom*/,
     bool /*directional_movement*/) {
   NOTREACHED();
 }
 
 void StartPageView::StartPageTilesContainer::NotifyFirstResultYIndex(
@@ skipping 125 matching lines @@
 
 void StartPageView::OnShown() {
   // When the start page is shown, show or hide the custom launcher page
   // based on whether it is enabled.
   CustomLauncherPageView* custom_page_view =
       app_list_main_view_->contents_view()->custom_page_view();
   if (custom_page_view) {
     custom_page_view->SetVisible(
         app_list_main_view_->ShouldShowCustomLauncherPage());
   }
-  tiles_container_->Update();
   tiles_container_->ClearSelectedIndex();
+  tiles_container_->set_num_results(tiles_container_->Update());
   custom_launcher_page_background_->SetSelected(false);
 }
 
 gfx::Rect StartPageView::GetPageBoundsForState(
     AppListModel::State state) const {
   gfx::Rect onscreen_bounds(GetFullContentsBounds());
   if (state == AppListModel::STATE_START)
     return onscreen_bounds;
 
   return GetAboveContentsOffscreenBounds(onscreen_bounds.size());
@@ skipping 152 matching lines @@
   // is enabled).
   if (event->type() == ui::ET_SCROLL && event->y_offset() < 0)
     MaybeOpenCustomLauncherPage();
 }
 
 TileItemView* StartPageView::GetTileItemView(size_t index) {
   return tiles_container_->GetTileItemView(index);
 }
 
 }  // namespace app_list